fix: brotli let for reassignment

[onevt]

Description

brotli is re-assigned on line 26

Additional context

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[patak-dev]

@Niputi something looks odd here, why brotli is initially false and then reassigned to false if it isn't supported? Should we remove this variable or add a comment that we may enable it in the future?

[Niputi]

looks like a mistake. should default to true as it goes to false when it's not supported

  // disable Brotli on Node<12.7 where it is unsupported:
  if (!zlib.createBrotliCompress) brotli = false

[patak-dev]

Yes, was it like that in the WMR version? Maybe they ended up disabling it globally because it didn't work as expected?

[Niputi]

looks like they defaulted to false but haven't given context on why https://github.com/preactjs/wmr/blob/7f96b821c41ed178643749be83d262bf9bc8de5c/packages/wmr/src/lib/polkompress.js#L13